The Cycle Life

The Mountain Bike You Want: Niner's IMBA ROS9+

Have you ever been given a box of candy and then told you can’t open it for a couple of months?

That’s exactly what happened at Bike Press Camp this June when Niner showed off what was, without question, the most exciting bike I’ve seen all year—and then informed me it wouldn’t be ready for the big time until August.

Thursday, Niner at last publically unveiled the ROS9+, a 4130 ChroMoly steel hard-tail mountain bike built around 29+ size wheels. As a refresher, these are normal diameter 29-inch wheels with standard hub spacing and three-inch wide tires. The 29+ blends the rolling speed and versatility of a standard 29er with the additional flotation and traction of a fat bike.

Surly launched the 29+ standard two years ago with its Krampus. And though the bike became an immediate cult classic and won over just about anyone who tried it, until now the company remains the only one to have pursued this mid-fat size (though we have heard murmurings from other brands). That’s surprising because while I love a full-fledged fat bike, 29+ seems like an excellent compromise that suits the majority of users better than a bike with four- or five-inch tires.

Niner seems to agree, and they have built a frame that looks to be quite a refinement on the Krampus platform. This bike is basically a complete revamp of the brand’s existing ROS9 to accommodate 50mm-wide Stan’s Hugo Rims mounted with three-inch-wide Surly Knard tires. Niner has kept the chain stays short for quick handling, and they’ve manufactured the frame with a 142x12 maxle dropout for torsional stiffness in the rear. They’ve also created a brand new 29+ specific fork with 15mm thru axle expressly for this bike.

To launch the bike, Niner has once again created a special edition built in conjunction with the International Mountain Bike Association’s (IMBA) World Summit, being held in Steamboat Springs, Colorado, from August 20 to 24. Niner has created only nine of the IMBA bikes, with special graphics, a single-speed build using the company’s Biocentric bottom bracket, and high-end carbon cockpit parts. They are auctioning each of the bikes off at The Pro’s Closet, and 100 percent of the proceeds will benefit IMBA. Each special-edition bike is valued at over $4,500.

In case you’re not lucky enough to score at auction, Niner will offer the ROS9+ in a three-star build with SRAM X1 1x11 drivetrain, Stan’s Hugo wheels, and Niner-branded alloy parts. It will sell for $3,000 and begin shipping later this fall.